Learn more about Revit 2019: https://autode.sk/WhatsNewRevit | Avoid inadvertently deleting elements from a model with a new warning that lists elements related to levels selected for deletion.
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Learn more about Revit 2019: https://autode.sk/WhatsNewRevit | Avoid inadvertently deleting elements from a model with a new warning that lists elements related to levels selected for deletion.
source